I have to answer my work phone whether I recognize the number or not, so I usually answer and immediately hit the mute button until I see who it is.
The spam callers will usually say “hello” a couple of times plus “can you hear me,” then hang up.
Yesterday, one of the usual idiots from India, said “hello” a couple of times then ended the call with “c**k sucker.”
I didn’t have time to unmute and say “do you know me?” 😜
They are getting so brazen.